The use of aluminum nitride fiber to impart anisotropic thermal properties to composite electronic substrates is described in U.S. Pat. No. 4,256,792. The present invention provides another fiber that functions in a similar manner and which is prepared by a novel process.
Condensation products of alkyl aluminum and aliphatic amines, hydrazines or aniline, are known in the art. One disadvantage of such products is that they are liquids or melt on heating to temperatures required for processing for end-use applications. One object of the present invention is to provide a new material which overcomes this deficiency.